Learn about the blood and nerve supply of the scalp, which has a rich blood supply from both internal and external carotid arteries and is supplied by 10 nerves on each side. Discover the specific arteries and nerves involved, their functions, and the potential consequences of nerve damage.
Blood Supply Of Scalp
The scalp is supplied with blood by several arteries, including the internal and external carotid arteries, which are two major blood vessels in the neck. The internal carotid artery gives rise to two branches, the supratrochlear and supraorbital arteries, which supply the front part of the scalp. The supratrochlear artery runs medially to supply the skin of the forehead, while the supraorbital artery runs superiorly to supply the upper part of the forehead.
The external carotid artery gives rise to two branches, the superficial temporal and posterior auricular arteries, which supply the side and back part of the scalp respectively. The superficial temporal artery runs along the side of the head, just above the ear, and gives off several branches that supply the temporal region and the scalp. The posterior auricular artery supplies the scalp behind the ear and is accompanied by the greater auricular nerve.
In addition to these arteries, the occipital artery also supplies the back part of the scalp and is a branch of the external carotid artery. This artery runs upward and backward to supply the occipital region and the scalp.
The blood supply to the scalp is important for providing oxygen and nutrients to the hair follicles, as well as for wound healing and preventing infections in the scalp. The blood vessels in the scalp also help to regulate body temperature by controlling blood flow to the scalp, which can either release or conserve heat. Overall, the blood supply of the scalp is an essential component of maintaining healthy hair and scalp function.
RELATED : Anatomy Of Scalp : In Depth Explanation
Nerve Supply Of Scalp
The scalp and temple are supplied by a total of 20 nerves, 10 on each side of the head. These nerves provide both sensory and motor functions, and are responsible for the feeling and movement of the scalp.
Five of these nerves (four sensory and one motor) enter the scalp in front of the auricle, which is the external ear. The sensory nerves are responsible for providing sensation to the skin of the scalp, while the motor nerve controls the muscles that are responsible for moving the scalp. The four sensory nerves that enter the scalp in front of the auricle are the supratrochlear, supraorbital, zygomaticotemporal, and auriculotemporal nerves. The supratrochlear and supraorbital nerves are branches of the ophthalmic nerve, which is a branch of the trigeminal nerve. The zygomaticotemporal nerve is a branch of the maxillary nerve, which is another branch of the trigeminal nerve. The auriculotemporal nerve is a branch of the mandibular nerve, which is the third branch of the trigeminal nerve.
The remaining five nerves (four sensory and one motor) enter the scalp behind the auricle. The sensory nerves provide sensation to the skin of the scalp, while the motor nerve controls the muscles that are responsible for moving the scalp. The four sensory nerves that enter the scalp behind the auricle are the greater occipital, lesser occipital, greater auricular, and lesser auricular nerves. The greater occipital nerve is a branch of the dorsal rami of the C2 spinal nerve, while the lesser occipital nerve is a branch of the cervical plexus. The greater auricular nerve is also a branch of the cervical plexus, while the lesser auricular nerve is a branch of the facial nerve.
Overall, the nerve supply of the scalp is a complex network of nerves that provide both sensory and motor functions. The nerves that enter the scalp in front of the auricle are responsible for providing sensation and movement to the front part of the scalp, while the nerves that enter the scalp behind the auricle provide sensation and movement to the back part of the scalp. These nerves are essential for maintaining proper sensation and movement of the scalp, and any damage to these nerves can result in scalp numbness, pain, or loss of movement.
Summary and Notes of Blood And Nerve Supply Of Scalp
Blood Supply
- The scalp has a rich blood supply derived from both the internal and external carotid arteries.
- In front of the auricle, the scalp is supplied by the supratrochlear, supraorbital, and superficial temporal arteries.
- The supratrochlear and supraorbital arteries are branches of the ophthalmic artery, which is a branch of the internal carotid artery.
- The superficial temporal artery is branch of the external carotid artery.
- Behind the auricle, the scalp is supplied by the posterior auricular and occipital arteries.
- Both the posterior auricular and occipital arteries are branches of the external carotid artery.
Nerve Supply
- The scalp and temple are provided by ten nerves on each side.
- Five nerves (four sensory and one motor) enter the scalp in front of the auricle, while the remaining five nerves (again, four sensory and one motor) enter the scalp behind the auricle.
- The sensory nerves provide sensation to the skin of the scalp, while the motor nerve controls the muscles that are responsible for moving the scalp.
- The four sensory nerves that enter the scalp in front of the auricle are the supratrochlear, supraorbital, zygomaticotemporal, and auriculotemporal nerves.
- The sensory nerves that enter the scalp behind the auricle are the greater occipital, lesser occipital, greater auricular, and lesser auricular nerves.
- The greater occipital nerve is a branch of the dorsal rami of the C2 spinal nerve, while the lesser occipital nerve is a branch of the cervical plexus.
- The greater auricular nerve and the lesser auricular nerve are both branches of the cervical plexus.
- Any damage to these nerves can result in scalp numbness, pain, or loss of movement.
